Pipe-wrench



(NoModeL) I M. JACKSON 81; F. ROBERTS.

. PIPE WRENCH. N0. 518,'818. Patented Apr. 24, 1894..

d 1.7 M M THE NATKONAL LIYHOGRIPIUNG COMPANY,

WASHINGTON, D. 04

Y NITEDI STATES PATENT OFFICE EDWIN M. JACKSON AND FRANK ROBERTS, OFCHICAGO, ILLINOIS.

PIPE-WRENCH.

SPECIFICATION forming part of Letters Patent No. 518,818, datedApril-24, 1894. Application filed January 8,1894. Serial No. 496,124.(No model.)

To all whom itmay concern:

Be it known that we, EDWIN M. JACKSON and FRANK ROBERTS, citizens of theUnited States, residing at Chicago, in the county of Cook and State ofIllinois, have invented certam new and useful Improvements in Pipe-Wrenches; and we do declare the following to be a full, clear, and exactdescription of the nvention, such as will enable others skilled in theart to which it appertains to make and use the same, reference being badto the accompanying drawings, and to the letters of reference markedthereon, which form a part of this specification.

Our invention relates to pipe wrenches. Its

object is to secure in an implement of this class great efficiency,convenience and'safety to the pipe. s

The invention consists of the use of two aws, one pivoted upon theother, and a handle in the form of a lever pivoted to one of the jawsand bearing as a cam, upon the other, so as to close the jaws together.

In the drawings, Figure 1, is a side elevation of the wrench. Fig. 2, isa plan view of the same. Fig. 3, is a longitudinal section on the line33 of Fig. 2. Fig. 4, is a detail.

The main jaw A, is in hook form,the inner surface of its upturned endbeing transversely serrated as shown ate, and the inner surfaces of itsstern and its transverse portion a, being fiat so that the pipe D, mayrest against them.

The jaw, B,is oblong in form and pivoted at one of its ends to the stemof the jaw A, at b, so as to fall across the mouth of the hook of thejaw, A. The forward face of the jaw B, is convex and transverselyserrated and is adapted to bear against the pipe and force it into theangle between the faces a, and a, of the jaw A.

The handle, or lever, C, is pivoted to the stem of thejaw A, at c,abovahr back of, the jaw B. The lever 0, projects beyond the pivotalpoint e, and is curved backwardly from the jaw B, so as to present to ita convex face, which is adapted to bear upon the back of the jaw B, andslide upon it asa cam, as the handle 0, is turned upon its pivotal pointso as to approach the alignment of the stem of the jaw A, and by thismovement the jaw B, is forced forwardly into contact with the pipe D,upon which the jaw A, has been previously hooked.

The wrench is so adj usted to the pipe to be turned that the strain uponits handle tends to the closure .of thejaws, so that the greater thestrain necessary to turn the pipe the more tightly does-the wrench gripthe pipe,

The form of the jaw A, as already described, is such that pressure isapplied to the pipe at and the face of the jaw B, so separated as tocover more than one-half of its circumference so that the danger ofcrushing the pipe is reduced to the minimum. The wrench is suitable forservice upon pipes extending from the smallest sizeto the full capacityof the hook ofthe jaw A. When the pipe is large the contact with the jawB, is near the pivotal point I), and the contact between the jaw B, withthe lever O, is near the end of the former so'that the leverage isgreat; when the pipe is small its contact with the jaw B, is near theouter end of the former and thepressure at the lever 0, upon the jaw isnear the pivotal point I), so that the pressure is divided between thepipe and this pivot pin. The curved form of the face of the jaw B,conduces' to this variation of the pressure with the size of the pipe. Aspring 6, is applied so as to hold the jaw B, in contact with the lever0, when not under pressure, and stop lugs f, are formed upon the sidesof the handle a little above the ,pivot pin'c, soas to limit thebackward fiex ure at this point. preferably longitudinally slotted sothat the jaw B, and the handle 0, are pivoted within the slot.

We claim as our invention 1. In a pipe wrench the combination with aV-shaped jaw, A, a clamping jaw, B, pivoted to one arm of the jaw, A, soasto extend across its mouth, a hand-lever, C, pivoted to the same armof the jaw, A, above thepivotal point of the jaw, B, and adapted to haveits toe end bear upon the back of said jaw B, substantially as describedand for the purpose specified.

three points, viz, at the face a, the face a, 1

The stem of thejaw A, is

2. In a pipe wrench the combination of a In testimony whereof we affixour signatures hooked jaw, A, a clamping jaw, 13, having its in presenceof two witnesses. face longitudinally convex and being pivoted to thejaw, A, so as to extend across its mouth, 5 a lever, C, of the firstclass, pivoted to the jaw, A, above, and adapted to bear upon the\Vitnesses: back of the jaw, B, substantially as described W. C.CORLIES, and for the purpose specified. LoUIs K. GILLSON.

